1. Technical Field
The present invention relates to a method of manufacturing an active matrix substrate, to an active matrix substrate, to an electro-optical device, and to an electronic apparatus.
2. Related Art
As portable apparatuses, such as notebook computers, cellular phones, and the like, have become wide spread, light and thin liquid crystal display devices have been employed therewith. According to this kind of liquid crystal device, a liquid crystal layer is interposed between an upper substrate and a lower substrate.
One example of the lower substrate (active matrix substrate) is shown in FIG. 17. As shown in FIG. 17, the lower substrate 1 includes a glass substrate 2, a gate scanning electrode 3 and a source electrode 4 disposed so as to cross each other on the glass substrate 2, a drain electrode 5 disposed on the glass substrate 2, a pixel electrode (ITO) 6 connected to the drain electrode 5, an insulating layer 7 interposed between the gate scanning electrode 3 and the source electrode 4, and a thin film transistor (TFT) 8 composed of a thin film semiconductor.
In formation of each metal wiring line in the lower substrate 1, for example, as disclosed in the Japanese Patent No. 3261699, a process combining a drying process and a photolithoetching process is repeatedly carried out several times.
However, since the above-described technique requires the process combining the drying process and the photolithoetching process to be carried out several times, it causes material cost or management cost to increase, and also makes it difficult to increase yield.
That is, a photosensitive material referred to as a resist is coated on a substrate where a conductive film is coated in advance, a circuit pattern is developed by irradiation, the conductive film is etched according to the resist pattern, and a thin-film wiring line pattern is formed. In addition, large equipment such as a vacuum device and a complicated process are required, and a usage effectiveness of the material is only several percent, and thus most of the material is wasted, which causes a manufacturing cost to increase.
Accordingly, it is required to reduce the number of processes in which the drying process and the photolithoetching process are combined in manufacturing a liquid crystal device which has been requested to have a low price in terms of its product cost.